Piston packing-ring.



W. G. DODD. PISTON PACKING RING. APPLICATION FILED SEPT. 3,1912.

Patented June 10,1913.

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W. e. DODD. v PISTON maxim mm APPLIOATIQH FILED SEPT. 8, 1912.

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Patented June 110, 19 13.

UNITED STATES PATENT OFFICE.

WILLIS DQDD, OF SAN FRANCISCO, CALIFORNIA.

PISTON PACKING-RING.

Application filed September 3, 1912. Serial No. 71Ei.339.

My invention relates to packing rings,

more particularly as applied to pistons and piston valves.

Themain object of the invention is to construct. an efficient, strong,safe and durable piston packing ring, adapted to operate under thehighest attainable pressures and temperatures of superheated-steam.

A further objectis to construct a piston packing ring, adapted tooperate under expansive tension, or contractive tension as desired, oras conditions may require.

A further ob 'ect is to construct a piston packing ring, to meet theconditions required, with the smallest possible number of joints andparts therein.

The means employed for accomplishing these objects are described in thefollowing specification, pointedout in the claims and illustrated in theaccompanying drawings, similar letters and numerals referring to similarparts. I

Merely for the purpose of illustration, a form of piston valve is shownin the accompanying drawings to which this invention is applicable, butit may be applied to other types and for other purposes, and nolimit-a.- tion with respect to the scope of the invention is implied byreason of the particular form of its application herein shown anddescribed.

In the drawings :F.igure 1 is an elevated viev' of a solid metal ring,dotted lines indicating proportionate thickness of the metal anddiagonal line of squares indicating metal to be,- or as cut. away. Fig.2 is an elevation of the ring shown in Fig. 1 after it has beencompressed and set, and shows the steam abutmcnts which have'been formedby the process, the inside dotted line representing a bull-ring. Fig. 3is a sectional view of a portion of the head of a piston valve, andshows the relative. position of the packing as applied to a pistonvalve. Fig. 4 is a view of a piston valve in part section fitted with myimproved packing. Fig. 5 is a sectional illustrative view of a steamcylinder and valve chest, with piston and valve Specification of LettersPatent.

shown as formed Patented June 10, 1913.

fitted with my improved packing, in operating osition.

In tie figures and letters of reference A. is a solid turned metal ringof any diameter, width and thickness required.

a. 7). a. (Z. 6, represent portions of the ring cut away or mortised outof the solid metal.

B. represents the ring A after it has been compressed and set, and by sodoing has formed the steam tight joints or abutments f. g. h. e. andleaving the spaces or openings 70. Z. m. n.

C. represents a metal bull-ring of the ordinary type and proportions,(with reference to the outside ring) which when out and inserted withinthe ring B has an expansive tension.

D. represents a portion of the head of a piston valve of the ordinarytype.

E. represents the fixed flange and G represents the removable flange,and between these two flanges the packing ring B and bull-ring C areshown in relative and normal position.

X represents a grove or port, formed in the outside of the bull-ring Cand is shown in communication with the opening 1 on line 0. 7). Fig. 2of the packing ring B.

T. represents an annular opening or space between the valve head and thebull-ring.

The method of constructing a packing ring as herein disclosed isas-follows :-Firstturn, bore and face the approximate size required, cutor mortise out the sections 0.. 7) c. (1.0., then beat the ring to acherry red heat. and press it into a metal mold of proper depth, havingan internal diameter of about one eighth of an inch less than theexternal diameter of the ring, let it remain until cold. then remove itand repeat the process. (each operation requiring a smaller mold) asmany times as necessary to form abutments f. g. h. 5., the ends of thering at j. and a. may now be secured by use of soft solder, and the ringtreated as a solid casting, turned, bored and faced to the finishedsize. 1

In the drawings Fig. 2, the ring B is for a contractive tension, andrequires a. substantial bull-ring with an expansive tension or someother controllable means suitable for expanding the pack- 1ifpg ring ltto the bore of the valve chammetal ring to the Should it be desirable tohave the packing ring operate under an expansive tension, the process ofcompressing the ring is not carried as far as when required for acontractive tension, but would stop when it substantially reached apoint indicated by the dotted lines, 6. 7. 8. 9. 10. Fig. 2. lhe ringwould now be sprung together, fastened with .soft solder and treated asa solid casting,

and be; turned, bored and faced to size, and a light bull-ring with verylittle expansive tension would be employed.

The construction as above described is preferable when the packing ringis of cast metal. If preferred the ring may be made of ductile metal, inwhich case spring steel is preferable, and a plate of suitable lengthand width is properly cut or notched at the ends, and is then rolledinto a ring, the notched ends coming together and forming the lap-jointsor abutments, and the ring thus formed is then treated as abovedescribed, but before being put into operation, it should be tempered inoil, to a degree of hardness, approximately that of the metal formingthe bore within which it reciprocates. For use in pumps this packingring may be, if desired, made of rubber or any suitable fiber.

In the operation of this packing ring it is desirable that it should bebalanced that is, the pressure inside the packing should be the same asthe pressure outside, and to provide for this, the grove X, is turnedout. in the bull-ring C. This grove communicates with the outsideopening Z as shown on line 0. 21. Fig. 2', thus affording directcommunication (through the inside cut of the bullring) to the smallspace between the packing and the valve head, thus providing forpressure balance required. Another important function is performed bythis grove, viz., when steam pistons are working in connection with avacuum it is desirable (and almost imperative) that oil should not beused for lubrication, and pistons under the conditions named operatewithout lubrication other than themoisture contained in the steam. lVithhigh superheat the amount of moisture is almost negligible and thepistons re ceive little or no lubrication. \Vith my steam packing, thespace T between the bullring and valve head is partially filled withpure graphite and in operation finds its way out in minute particlesthrough the grove in the bullring and thus aifords the much neededlubricant.

The method of constructing a piston packs ing ring as herein disclosed,admits of providing a packing which meets all the conditions requiredfor operating under the! highest practical temperatures of superheat,affords perfectly steam tight abutments, may i be operated underexpansive or contractive tension as desired, enabling it to be fitted tothe working bore at any degree of friction pull desired, and it can beconstructed in the most substantial manner, of any rnaterial, thusinsuring perfect safety in operation ashore or afloat.

Having thus described my invention, I claim 1. A piston packing ring,consisting of one piece of material, having a plurality of integral lapjoint or abutments.

2. A resilient piston packing ring, consisting of one piece of materialhaving a se, ries of lap-joints or abutments formed in-' tegral with thering itself.

3. A piston packing ring, consisting of one piece of material providedwith a plurality of integral lap-joints or abutments,'in combinationwith a bull-ring as and for the purpose described.

In testimony that I claim the foregoing I have set my hand this 28th dayof August, 1912, in the presence of witnesses.

W. G, DODD.

Witnesses:

F. F. ALEXANDER, A. B. CRAIG.

